Sound absorbing construction



NAV. 24, 1931.

H. F. WEISS SOUND ABSORBING CONSTRUCTION Filed June 8, 1929 vayan/04" 5 It is anobject of this invention to provide ama iai 1,833,143

UNITE-D- sTATEs? PATEN-r OFFICE I y HOWARD 1". WEISS, O F MADISON, WISCONSIN, 'ASSIGIWOR TO C. I BUBGEBS LABORA- TORIES, ING., OF MADISON, WISCONSIN, A CORPORATION 0F DELAWARE som nsomsma eons'rnucrmr 1 application ma :une s, im. serial m. 369,410.

This invention relates to sound-absorbing construction. It relates especiallyto that type of sound-absorbing construction which has .a foraminous membranev for a facing.

may be a metal sheet, is provided with openings or perforations 2. I place on this foraminous membrane a second membrane comprising a sheet havin ruptured projecting portions 4 which. are 1n contact with the first' forammous membrane and thereforespace ther 'second membrane from the lirst membrane. The ruptured projecting portions may be made by a punching operation, using a tapered punch. The punching is deen enough so that the projecting portions are ruptured at one or more places, thereby allowing l,the sound waves to penetrate therethrough andr reach the sound-absorbing material 5 which is placed on top of the second membrane. e5' faced with a foraminous membrane and esvThe projectingporti'ons also are.stii enough pecially a stiff membrane such-'asperforated l to act as spacers.

sheet metal or the. like, -it is necessaryto have The ruptured membrane preferably is a the' sound-absorbing material in the` form of fibI'OuS Sheet Such as .heavy paper but where' a block, pad or a felt so that the bers 0r a` ireproof construction isv necessary this 55 a sound-absorbing) constructlon 1n whlch the sound-absorbing acking f or a foraminous facin may consist of packed librous or other soun -absorbing material.whicl1 need not 10 have been made up into pads or the like. It

isa further object 4to providexan improved spacing material between the foraminous facing and the sound-absorber.

n the type `of sound-absorbingl construction in which asound-absorbing material is other materials constituting thisv sound-absorbing materialare bound'togetherand do not ydrop through the perforations Jto the annoyance of the occupants of the room.v If the sound-absorbing material is in direct contact with the oraminous membrane another` difculty sometimes arises when the exposed surface. of the membrane is washed and cleaned 'orjwhen it is painted, namely, 'the' water, cleaning material or paint soaks into the sound absorbing-material which is 'ex-1 posed at theo enings, causing, said material to lose some o its sound-absorbing property.

. The perforations of'the membrane are `also frequently clogged by the decorating;y mate-Y rial, if the latter is not applied properly. In addition vthe'foraminous membrane does not appear to be uniformly colored when' viewed by the occupants of the room, where there is uneven contact.between the absorber and membrane. I have overcomethese difficulties with my improved construction, two embodiments of Which are shown in the drawings', wherein Fig. 1 is an enlarged. broken sectional view illustrating one form of the invention, and

Fig. 2 is-a modified construction.

' Fig. 3 isa lan viewof a porticnfof the L ruptured mem rane.

o In Fig. 1 a forammous-membrane 1, which -ton, shred sheet may be of thin asbestos or other fire resistant material. This membrane is preferably treated by an suitable material or process so as not to a sorb liquids so that it does not get soggy and collapse if itis exposed to aV moist atmosphere or if paint comes in contact Vwith it through perforations in the first 'membrana should be placed close enoughtogether -so` that the sheet will be stiff enough to withl stand the weight of the sound-absorbing material without sagging and'com'inggin contact 'with the first membrane. The Holes should also be close enough together so'the sound-absorbing value of the sound-absorb- As a spein construct-ion is. not lowered. ci c example, a tapered 1,;square punch long used on 1,11 'centers givesexcellent results with thinasbestos paper. The soundabsorbin materialmayxbe any suitable material. f fibrous substance suitable for fireproof construction is a mineral fiber such Vas slag wool or asbestos. used. Granular substances such as exfoliated zpnolite, sized umice and the like are suitable.- Wherea reproof construction is unnecessary/shredded wood bers, wool, coted pulp, etc., may be used. To erect my improved lsound-absorbing constraction the foraminous membranel is 100 M The projecting portions` Steel wool maybe A first ,fastened in` p means. The secon membrane 3, pre erably with ruptured projecting portions 4, is then placed on the first membrane with the projec- 5 tions in contact therewith. The sound-absorbing material 5 is then packed lback of membrane 3 if it has not been felted or otherwise stuck together into a pad o'r unit. lThe absorbing material need not be previousl felted or otherwise lformed. into v`pads. have found `that my construction effectively retains, the unfelted sound-asborbing material and prevents it from and sifting throu h the perforations in the first membrane. urthermcre, when the first membrane is decorated the paint does not reach the sound-absorbing material and the holes arenot plugged as is' the case when the absorber or a sheet lies fiat upon it. The sec- Filg, e though I have shown and described certain modifications of my improvements for the purpose of illustration, Ido not wish to 'brane be restricted specilicall thereto except asso limitedby the appendeciclaims. n f Ix'claim:

I'. A vsound-absorbing construction compnsmg in combination' a foraminous memrane, a backing of sound-absorbing material,

vand a second foraminous membrane therebe- 5 `tween having projecting portions,- said proportions `spacing said second rane fronsaid Afirst membrane.

2. A sound-absorbing construction comrising in combination a foraminous mem- 5 rane, a backing of sound-absorbing material,

' and a second membrane therebetween comprising a sheet having ruptured projecting portions, said, projectilg POUDS. 5Pwin8.

said second 'U5-brane. Y

3. A .sound-absorbing conruction comprising in combination a perforated sti 'membrane abac of soun -absorb' material, a secon foraminous m rane '0 therebetweenA comprising a foram'inous brons sheetv having projecting portions,

said ro'ectmg' said second said sa maj-.humbug mssen son;

prising `in combinations foraminous memlace by any ap roved,

rane", a b' ond membrane when made as specified doesA u not interfere, with the :sound-absorbing memmembrane from rst mem- P0115 ported by said first membrane for spacing* means lprising a non-liquidabsorbing sheet having ruptured projecting portions, said projecting. portions spacingisai second membrape'from saidfirstmembran' i Y 5. A- sound-absorbing construction comprising in combination a foraminous memaclnn' gof sound-absorbingmaterial and a second membrane therebetween com-- prising an asbestos'sheet having ruptured projecting; portions, said projecting portions y spacing sal membrane. ,Y v

6. ,A sound-absorbing construction comprising in-combination a perforated sheet metal membrane, a backing .of tire-resistant second membrane from said first Asound-absorbing material, and a second membrane therebetween comprising a oraminous asbestos sheet having projecting portions, said projecting portions spacing said second membrane from said first membrane.

I. A. sound-absorbing construction comprising in combination a foraminous membrane, a-backing of non-felted soundlab/sorbing material, and a second membrane therebetween comprising a non-liquid-'absorbent sheet having ruptured projecting portions said project-mg portions spacing said secon mem rane from said first membrane.

8. A sound-absorbing' construction comprising in combination aperforated sheet metal membrane, a backin of mineral fiber, and a second membrane erebetween comprising Ia. foraminous., asbestos sheet having pro'ecting' portions, id tportions spacing said second membran from said iirst mem- 9. In a soundabsorbing construction comprising a -fo'raminous membrane, asound-absorbing backing', and means for spacing said backing from said membrane comprising a foraminous sheet having projecting portions.

sorbing backing,iandl means for spacing said backing from said membrane comprising an sheet having ruptured projecting long, v

' 12. A sound-'ibsorbing construction comrising, in combination, a foraminous memrane, sound-absorbing material atthe rear thereof, a second fgrammous supported membrane therebetween, and means directly supsaid second membrane from the first mem- In testimony whereof, I have subscribed my name. L

HOWARD F; no,

Gammons 0F CORRECTION.`

ynieuwe.1,833,143x j p lGranted November 24, 1931,11l

f HOWARD F. WEISS. Y

It is hereby, certified that error appears in the printed specification of the above numbered` patent requiringncorrection as iollowsz, Page 2, line. 123, claim.

i2.' strike out the word "support-ed'v; and that. the said Letters Patent should bel read with this correction therein th'at the same may conform to the rrecord of the case in the Patent Office. y

Signed 'and sealed this 16th day of February, A. D. 1932.

g M. J.

, (Seal) I Acting Commissioner of Patents# 

